Mathematics is merely the means to a general and ultimate knowledge of man.

We must repay goodness and wickedness: but why exactly to the person who has done us a good or a wicked turn?

It says nothing against the ripeness of a spirit that it has a few worms.

A casual stroll through the lunatic asylum shows that faith does not prove anything.

I have forgotten my umbrella.

One must not let oneself be misled: they say 'Judge not!' but they send to Hell everything that stands in their way.

Man is more sensitive to the contempt of others than to self-contempt.